Poojari Avinash, Sapru Shantanu, Khurana Rohini, Rastogi Madhup, Hadi Rahat, Gandhi Ajeet Kumar, Mishra Surendra, Srivastava Anoop, Bharati Avinav
Radiation Oncology Dr Ram Manohar Lohia Institute of Medical Sciences.
Precis Radiat Oncol. 2023 Jun 25;7(2):118-127. doi: 10.1002/pro6.1203. eCollection 2023 Jun.
To compare volumetric modulated arc therapy (VMAT) with simultaneous tumor bed boost (dpSIB-VMAT) to the whole breast and regional nodal irradiation (RNI) against standard three-dimensional conformal radiotherapy plus RNI with sequential tumor bed boost (3D-CRT-seqB).
Thirty patients who underwent breast cancer surgery (BCS) with axillary lymph node dissection (ALND) were enrolled. Two plans were generated for each case: (1) dpSIB-VMAT, and (2) 3D-CRT-seqB plans. Planning target volume (PTV)-Breast and PTV-Nodes were prescribed at a dose of 50 Gy in 25 fractions in both plans. PTV-Boost was prescribed at a dose of 60 Gy in 25 fractions simultaneously in the dpSIB-VMAT plans, whereas it was planned sequentially in the 3D-CRT-seqB plans at 10 Gy in 5 fractions. Dosimetric parameters were compared between the two plans.
Both plans achieved the target coverage. D of the heart was lower with dpSIB-VMAT in left-sided cases (7.17 ± 0.66 Gy vs. 10.12 ± 2.91 Gy; = 4.02; = 0.001). Ipsilateral mean lung dose (15.87 ± 1.40 Gy vs. 19.82 ± 3.20 Gy; = 6.30; <0.001) was significantly lower but mean doses of the contralateral breast (4.30 ± 1.76 Gy vs. 1.48 ± 0.76 Gy; = -7.84; <0.001), contralateral lung (3.86 ± 1.21 Gy vs. 0.96 ± 0.25 Gy; = -13.13; <0.001) and esophagus (13.11 ± 2.63 Gy vs. 10.32 ± 3.56 Gy; = -6.65; <0.001) were relatively higher with dpSIB-VMAT.
Dosimetrically, dpSIB-VMAT reduced doses to the ipsilateral lung and heart (in left breast but not right breast cases) compared to 3D-CRT-seqB plans for adequate target coverage.
比较容积调强弧形放疗（VMAT）联合同步瘤床加量（dpSIB-VMAT）对全乳及区域淋巴结照射（RNI）与标准三维适形放疗加RNI序贯瘤床加量（3D-CRT-seqB）的效果。
纳入30例行乳腺癌手术（BCS）并腋窝淋巴结清扫（ALND）的患者。为每个病例制定两个计划：（1）dpSIB-VMAT，（2）3D-CRT-seqB计划。两个计划中，计划靶区（PTV）-乳腺和PTV-淋巴结的处方剂量均为50 Gy，分25次照射。在dpSIB-VMAT计划中，PTV-加量区同时处方剂量为60 Gy，分25次照射，而在3D-CRT-seqB计划中，其计划为序贯加量，5次照射，每次10 Gy。比较两个计划的剂量学参数。
两个计划均达到靶区覆盖。左侧病例中，dpSIB-VMAT使心脏的D值更低（7.17±0.66 Gy对10.12±2.91 Gy；t = 4.02；P = 0.001）。患侧平均肺剂量显著更低（15.87±1.40 Gy对19.82±3.20 Gy；t = 6.30；P<0.001），但dpSIB-VMAT时对侧乳腺（4.30±1.76 Gy对1.48±0.76 Gy；t = -7.84；P<0.001）、对侧肺（3.86±1.21 Gy对0.96±0.25 Gy；t = -13.13；P<0.001）和食管（13.11±2.63 Gy对10.32±3.56 Gy；t = -6.65；P<0.001）的平均剂量相对更高。
在剂量学方面，与3D-CRT-seqB计划相比，dpSIB-VMAT在实现充分靶区覆盖的同时，降低了患侧肺和心脏（左侧乳腺病例，右侧乳腺病例未降低）的剂量。
